jiachen247

# https://leetcode.com/problems/search-insert-position/

class Solution(object):
    def searchInsert(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: int
        """
        l = 0

jiachen247

"""
Clean historical bitcoin price data
- from min to 12 hours
"""

source_fn = 'bitstampUSD_1-min_data_2012-01-01_to_2021-03-31.csv'
dest_fn = 'bitstampUSD_12-hours_data_2012-01-01_to_2021-03-31.csv'

# source = open("bitstampUSD_1-min_data_2012-01-01_to_2021-03-31.csv", "r")
# dest =  open("bitstampUSD_12-hours_data_2012-01-01_to_2021-03-31.csv", "w+")

jiachen247

def twoSum(nums, target):
  seen = {}                  
  for i in range(len(nums)): # O(N)  
      if (target - nums[i]) in seen: # O(1) 
        prev = seen[target - nums[i]]
        return [prev, i]
      else:                     
          seen[nums[i]] = i  #O(1)

print(twoSum([2, 13, 16, 8], 10))

jiachen247

def mergeSort(arr):
  def combine(L, R):
    i = j = k = 0
  
    while i < len(L) and j < len(R):
      if L[i] < R[j]:
        arr[k] = L[i]
        i += 1
      else:
        arr[k] = R[j]

jiachen247

// $ node index.js celcius fahrenheit 1 2 3
const CELCIUS = "celcius";
const FAHRENHEIT = "fahrenheit";

const source = process.argv[2];
const dest = process.argv[3];
process.argv // ['node', 'index.js', 'celcius', 'fahrenheit', '1', '2', '3']
  .slice(4) // ['1', '2', '3']
  .map(s => parseInt(s, 10)) // [1, 2, 3]
  .map(convert) // [33.8, 35.6, 37.4]

jiachen247

#include <iostream>
#include <vector>
#include <string>
#include <fstream>
#include <ctype.h>

using namespace std;

// === LEXER === // 

jiachen247

LLVM Sauce Nix Setup

For Nix we require some extra packages. Use this shell.nix, it gets you everything in one shot:

with import <nixpkgs> {};

pkgs.stdenv.mkDerivation rec {
  name = "yarn";
  buildInputs = with pkgs; [
 xorg.libX11

jiachen247

🍊 LLVM Sauce VM Setup Guide

Note: Alternatively, you can spin up a AWS EC22 t2.micro instance and skip steps 1 and 2!

Step 1: Download Ubuntu ISO

• Download Ubuntu 20.04.2.0 LTS from https://ubuntu.com/download/desktop

Step 2: Create a VM

• Using VirtualBox or another virtualization tool, spin up a VM using the Ubuntu ISO just downloaded from step 1
• Provision at a hard disk with at least 40 GB

jiachen247

// Source Program

const x = 1;
{
    const x = 2;
    if (x * 2 === 4) {
        display("Hello world!");
    } else {
         display("boo");
    }

jiachen247

def count_water(walls):
    n = len(walls)
    stack = list() # use a list as a stack
    stack.append((walls[0], 0)) # base case
    
    # go over the list of walls once
    for i in range(1, n):
        current_wall_height = walls[i]
        prev_wall_height = stack[-1][0]